         full-lengths (Math/floor (/ missing (.length padding)))
         remaining (if (zero? full-lengths) (- width (.length s))
                       (rem missing (* full-lengths (.length padding))))]
-    (.concat (apply str (repeat full-lengths padding))
-             (.substring padding 0 remaining))))
+    (str (apply str (repeat full-lengths padding))
+         (.substring padding 0 remaining))))
 
 
 (defn ^String pad-right

    :post [(= (.length %) width)]}
   (if (<= width (.length s))
     s
     (.concat s (gen-padding s padding width)))))

(defn ^String pad-left
  "Pad the beginning of s with padding, or spaces, until the length of

    :post [(= (.length %) width)]}
   (if (<= width (.length s))
     s
     (str (gen-padding s padding width) s))))

(defn ^String center
  "Pad both ends of s with padding, or spaces, until the length of s
